Oxide-Confined VCSELs for High-Speed Optical Interconnects

The electrically pumped vertical-cavity surface-emitting laser (VCSEL) was first demonstrated with metal cavities by Iga (1979); however, the device threshold current was too high. Distributed Bragg reflector cavities proposed by Scifres and Burnham (1975) were adopted to improve the optical cavity loss. Yet, it was not a practical use until the discovery of the native oxide of AlGaAs and the insertion of quantum wells to provide simultaneous current and optical confinement in semiconductor laser by Holonyak and Dallesasse (1990). Later, the first "low-threshold" oxide-confined VCSEL was realized by Deppe (1994) and opened the door of commercial application for a gigabit energy-efficient optical links. At present, we demonstrated that the oxide-confined VCSELs have advanced error-free data transmission [bit-error rate (BER) <= 10(-12)] to 57 Gb/s at 25 degrees C and 50 Gb/s at 85 degrees C, and also demonstrated that the pre-leveled 16-quadrature amplitude modulation orthogonal frequency-division multiplexing data were achieved at 104 Gbit/s under back-to-back transmission with the received error vector magnitude, SNR, and BER of 17.3%, 15.2 dB, and 3.8 x 10(-3), respectively.